Leachate collection and removal systems

National capacity variance When developing a treatment standard, U.S. EPA examines the available treatment capacity to determine whether it is sufficient to handle current and future waste management needs. If U.S. EPA determines that nationally there is not enough capacity to treat a waste, it can automatically extend the effective date of the waste s treatment standard. Such an extension to the effective date is intended to give the waste treatment industry more time to develop the capacity to handle the waste. Wastes under a national capacity variance can be disposed of, without meeting the treatment standards, in landfills and surface impoundments that meet minimum technical requirements (e.g., liners, leachate collection and removal systems, and leak detection systems). 

The site conditions for an on-site landfill, such as location, geology, hydrogeology, physiography, climate, and so on, should also be suitable. Landfill should meet the minimum technology requirements and regulations for hazardous waste landfills such as double liners and leachate collection and removal systems, leak detection systems, closure procedures and final cover, and construction quality assurance.59... 

Percolation monitoring can also be evaluated indirectly by using leachate collection and removal systems. For landfills underlain with these systems, the amount and composition of leachate generated can be used as an indicator of the performance of a cover system (the higher the percolation, the more leachate that will be generated).22... 

Finally, if high-level waste is considered to be hazardous waste under RCRA, requirements on construction, operation, and closure of a disposal facility, including the provision of a liner system, leachate collection and removal system, and leak detection system (see Section 4.2.2), would need to be addressed. Such requirements are impractical at a geologic repository for disposal of high-level waste... 

Environmental regulations dictate that landfills and surface impoundments for the disposal of hazardous and non-hazardous waste have liners (base, side-slope, and cover liners) and a leachate (contaminated water that emanates from a disposal site) collection and removal system in order to protect air, water, and land resources. Base and side-slopes of containments are lined with compacted clay or geomembrane (commonly HDPE) or both. Cover liners generally incorporate a foundation material overlain by a clay and/or geomembrane (commonly VLDPE which is more flexible than HDPE) liner. Geosynthetic clay liners may be used in place of clay. The leachate collection and removal system is... 

The landfill must have a double liner system that can prevent any migration of wastes out of the landfill to the adjacent soil, groundwater, or surface water. The liner system must include a leachate collection and removal system between the two liners. 

Operators must monitor and inspect the landfill during operation to ensure, for example, that the leachate collection and removal system operates correctly. 

Modern landfill facilities, waste lagoons, and leachate ponds use geotextiles in their key designed systems to contain wastes within the facility. The main designed systems are groundwater and gas collection systems underneath the base liner system, typically consisting of a leak detection system and a leachate collection and removal system, and within the final cover system to collect gas and water below and above the barrier system, respectively. 

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